Asthma is a common respiratory system disease, the pathogenesis includes: allergic response, airway chronic inflammation, airway hyperresponsiveness, airway neuroregulation disorder, genetic mechanism, respiratory tract virus infection, neural signal transduction mechanism, airway remodeling, as well as interactions thereof, etc. The main symptoms are paroxysmal gasping, panting, chest tightness or coughing, and the like, or original symptom rapid aggravating that usually accompanied with breathing difficulties featured by reduced expiratory gas flow, commonly induced by contacting allergen, irritant or respiratory infection. The symptoms may vary in severity, if the patient's condition is getting worse, it may appear within several hours or several days, and occasionally it may be life-threatening within several minutes. In recent years, allergic asthma induced by various allergens (such as pollens, dusts and dust mite) attracts more and more attention. Therefore, research on medicines for effectively against asthma has also become one of the primary research topics in the field.
The present inventor discloses in Chinese patents CN1194986C and CN1216075C a peptide shown in SEQ ID No.1 or a derivative thereof (abbreviated as 7P peptide or a derivative thereof, named as SP peptide or a derivative thereof in the present invention), which is an immunogenic peptide originally designed according to hepatitis C virus. In addition, it is proved that the 7P peptide or the derivative thereof has functions of inducing cytokines, such as r-IFN, IL-4 and IL-10 to an increased level and producing antibodies. r-IFN is a Th1-secreted cytokine, which is one of the primary cytokines of human immune system against virus infection, and it has a prominent meanings for the clearance of HCV (hepatitis C virus), so that the 7P peptide or the derivative thereof has functions of preventing and/or treating hepatitis C. Further, the present inventor discloses in patent application CN101822816A the application of the 7P peptide or the derivative thereof for preventing and treating pneumonia, and specifically records the 7P peptide or the derivative thereof for treating pneumonia by reducing TNF-α level. Therefore, it can be known from a report of the existing research that, the 7P peptide has functions of reducing TNF-α level of a patient with pneumonia, as well as promoting the cytokine IL-4 level of a patient with hepatitis C.
There are no reports about whether the peptide or the derivative thereof has effects on preventing asthma attacks and alleviating asthma symptoms.